(a) Field of the Invention
The present invention relates to an electrostriction motor and more particularly, it relates to an electrostriction motor which can be driven generating vibrating waves (or standing waves) when a cycle voltage of single phase is applied.
(b) Prior Art
Various kinds of motors which use electrostriction elements have been proposed. One of them firstly proposed by Japanese Patent Preliminary Publication No. 58-148682 produces linear or rotation movement using progressive waves which are composed of longitudinal and transversal waves excited on the phase boundary of an ultrasonic oscillator. This motor using ultrasonic vibration makes it necessary to apply two or more cycle voltages, different in phase, to the electrostriction element for the purpose of generating the progressive waves which are composed of the longitudinal and transversal waves. However, a complicated power supply circuit is needed to obtain the cycle voltages which are different from each other in phase. Further, a complicated wiring is also needed to apply the cycle voltages to the electrostriction element which is polarized in a specific direction.